Effects of restricted methionine and energy intake on egg weight and shell quality : research note

Authors

• T. KIISKINEN
• E. HELANDER

DOI: https://doi.org/10.23986/afsci.5615

Abstract

An experiment involving two laying hen hybrids and four dietary treatments was conducted to study the effects of dietary methionine restriction (MR) (3,05 g/kg, MR 100MR did not significantly affect hen-day production (%) but reduced linearly (P<0.001) egg weight. Average egg weights were 64.0 (MR 100), 63.1 (MR 87) and 60.6 g (MR 74). ER reduced egg weight to the same extent as MR 87 but its percentage laying was lower (P<0.05) than MR 87. Due to decreased egg weight feed conversion was considerably poorer for MR 74 than MR 100. Interactions between restriction and hybrid for egg production and feed intake, indicate differences in the requirements of methionine and energy between the two laying hybrids. Significant differences in shell quality were only observed between hybrids. However, the results concerning shell defects and shell quality parameters (shell strength, specific gravity) indicated an improvement for MR 74. In the classification of eggs MR increased linearly (P<0.001) the proportion of first class eggs, decreased the proportion of large (63B73 g) and extra large (>73 g) eggs, but increased medium (53B63 g) and small (<53 g) sized eggs. ER did not significantly affect the proportion of eggs in the quality classification, but did significantly (P<0.05) reduce the proportion of extra large eggs. The results suggest that methionine restriction is an effective means for reducing egg weight which may also improve shell quality.;